CA1085853A - 1-benzazolylalkyl-4-substituted-piperidines - Google Patents

Abstract

NOVEL 1-BENZAZOLYLALKYE-4-SUBSTITUTED-PIPERIDINES.

ABSTRACT OF THE DISCLOSURE:

Compounds of the class of 1-(benzazolylalkyl)piperidine derivatives, useful as neuroleptic agents.

Description

BACKGR OUND OF THE INVENTION: .

Ir the prior art there may be fou~d some l-(diaLlcylaIr.ino-aL~cyl)-l, 3-dihydro-2H-benzimidazol-2-ones ~ncluding 1, 3-dihydro-2H-benzimidazoi-2-ones having antidepressant and a~ticonvulsal:Lt properties. Among other points of difference the compou~ds of this .
, , ,, :- ,~
.. . .

: , ., , -, :

, .. . . . .
, , ~ . : , , . , . . , .~:
, ~ : :: :

;i8~ 3 invention differ from such known con~pounds by khe nature o~ the 4-substituted piperidine nucleus.

A number of the aforementioned prior art compounds may be found in the following references:

Int. Pharmacopsychiat. 1968 (1), p. 214;
C.A. 9 64, 2093b (1966); and C.A., 72, 111466 (1970).

DES CR IPTION OF THE PR E:FERR ED EMBODIMENTS:

The novel l-benzazolylalkyl-4-substituted-piperidine~ of this invention may structurally be r.epresented by the f~rmula:
R

~~(CH2)n N~}Q ~~

~=J\ 2 (I) and the pharmaceutically acceptable acid additiosl salts thereof, where-i~: , R is a member selected from the group consisting of hydrogen and halo;

Rl and R2 are each independently selected from the group consisting of hydrogen, halo, lower alkyl and trifluoromethyl;

n is an integer of from 2 to 4 inclusi~e;

Q iB a rnember selected frorn the group con8isting of C=O, oC(OR )2 and ~C~ (CH2)m wherein R i8 lower alkyl and m is an integer of from 2 to 3 inclusive; and A i6 a bivalent radical selected from the group consisting of O S O O
Il 11 11 Il , ,.~
-NH-C-, -NH-~, -O-C-, -S-C- and -N=C(L)-wherein L is selected from the group consi6ting of hydrogen, lower alkylthio, cycloalkyl and phenylmethyl, said bivalent radical being attached to the benzene nucleus by its hetero-atom, ; .
A~ used herein ~lower alkyl~ rnay be straight or branch chained and have from 1 to about 5 carbon atoms, such as, for example, methyl, ethyl, propyl, (l-r~Lethylethyl), butyl, pentyl and the like; and the term halo is generic to halogens of atomic weight less than 127; i. e., fluoro, chloro, bromo and iodo.

Compounds of formula ( I ) wherein R, R l, R2, Q and n are as prse~iou~ly defined and A iB as previously defined but other than C-, ~aid A being represented by A and said compounds by the formula (I-a), can be prepared by reacting an appropriate interrnediate of formula (II) wherein Rl, R2, Al and n are as previou~ly defined and wherein W is an appropriate reactive ester function derived fro~n the corresponding alcohol, such as, for example, halo, methanesulfonyl, 4-~nethylbenzenesulfonyl and the like, with an appropriate piperidine derivative of formula ( III ) wherein Q and R are previously defined, :
according to common N-allcylating procedures known in the art.

lOB5~353 ~~(C~Z)n~W + HN~}Q~

~,1 R2 ( III ) (II) R

A N~(CH2)n~N3 ~X, , '.
R R

( I-a ) The foregoing condensation reaction is, carried out, preferably, in an appropriate organic solvent, such as, for example, a lower alkanol, e. g. methanol, ethanol, propa~ol, butanol and the like alcohols; and aromatic hydrocarbon, e. g. benzene, methylbenzene, dimethylbenzene, and the like; a ketone, e. g. 4-methyl-2-pentanone; an ether, e. g.
1, 4-dioxane, 1,1 ' -oxybis ethane and the like; N , N-dimethylformamide;
nitrobenzene; and the like. The addition of an appropriate base, such as, for exa~nple, an all~ali metal or earth alkali metal carbonate or hydrogen carbonate, may be u~ilized to pick up the acid that is liberated during the coursc of the reaction. A small amount of an appropriate metal iodide, e. g. sodium 05 potassium iodide, may be added as a reaction promotor, especially when the reactive ester of formula ( II ) is a chloride.
Somewhat elevated temperatures are appropriate to enhance the rate of the reaction and preferably the reaction is carried out at the reflux temperature of the reaction mixture. In this and following procedures, the reaction products are separated from the medium and, if necessary, further purified by the application of methodologies known in the art.
`

5~3 The compounds of formula (I) wherein R, Rl, R2, n are as previously defined, Q is ~C--O, and A. is -NH-CO-, (I-b), may also be prepared starting from the corresponding intermediate of formula ( IV ) wherein P is an appropriate protecting group by the removal of the latter following conventional procedures. Examples of such protecting groups are, lower alkyloxycarbonyl and, a sub-stituted ethenyl group o the formula:

R5-CH=f-R
wherein R4 and R5 may represent different .:
groups but wherein R is preferably lower .
alkyl and R5 is preferably hydrogen, lower alkyl or phenyl.
;
When the protecting group is a lower alkyloxycarbonyl group, ~-it may easily be removed by allcaline hydrolysis, and when the protec:-ting group is a substituted ethenyl group it i6 conveniently eliminated by 6ubjecting the appropriate internlediate of :Eormula ( IV ) to acid r,~' hydrolysis.

P-~~(CH2)n~

~X ~ ',''~;
Rl R2 (IV) eli~nination of protecting group P :~:

HN~ (CH2)n~~

R ( I-b ) In carrying out the acid hydrolysis to remove the substituted ethenyl group from ( IV ) a wide variety of protonic acids rnay be employed including mineral acids, such as, for example, hydrochloric, hydro-bromic9 sulfuric, nitric and phosphoric acid, and organic acids, such .
as, for example, acetic acid, propanoic acid and the like. Further the reaction may be carried out in reaction-inert organic solvents as commonly employed in such a type of hydrolytic reactions, e. g.
methanol, ethanol, 2-propanone and the lilce.

.
Compounds within the scope of formula ( I ) which may be represented by the formula: .
R

~J (CH2)n N3Q~

( I-c 3 wherein R, R ,R2, n and Q are as previously defined and A2 is selected from the group consisting of -NH-CO-, -NH-CS-; and -N=C(L )-wherein said L is selected from the group consisting of hydrogen, cyclo-alkyl and phenylmethyl may still be prepared by subjecti~g an appro-priate benzenediamine of formula ( V ) to ring closure with an appropr-iate cyclizing agent, the nature of which depends on the nature of A2 in the desired product.
R

2 ~H_(cH2)n_N~}Q~ ring closure > ( I-c ) R l R 2 51~3 The foregoing cyclization reaction may be performed following art-known procedures of preparing lH-benzinlidazoles, 1, 3-dihydro-ZH-benzimidazol-Z-ones, and 1, 3-dihydro-2H-benzimidazol 2-thiones star-ting from 1, 2-benzenediamines. Suitable cyclizing agents which may ad-vantageous ly be employed to prepare compounds ( I- c) wherein A2 stands for -NH-CO-, include, for example, urea, carbonyl dichloride and alkali metal isocyanates, and the cyclization reaction may be carried out follo-wing methodologies generally known in the art.
For example, when urea is used a~ the cyclizing agent the desired compounds are easily obtained by stirring and heating the reac- ;-~
tants together in the absence of any solvent.
When A in the desired compounds (I-c) stands for -NH-CS-, there may be used cyclizing agents such as, fsr example, carbon di-sulfide, thiourea, carbonothioic dichloride, arnmonium thiocyanate and the like.
When A stands for -Ncc(Ll)- and when said Ll is hydrogen there may be used formic acid or an appropriate tri(alkyloxy)methane as a cyclizing agent. When said Ll in said -N=C(L )- is cycloalkyl or phenylmethyl, one may use as a cyclizing agent a carboxylic acid of the formula:
R -COOH
( ~TI ) wherein R5 iR respectively cycloalkyl or phenyl~nethyl, or a functional derivative thereof such as, for example, an acyl halide, an ester, an amide or a nitrile derived from such acid, or an iminoester of the formula:
~O-(lower alkyl) HN (~ R S -( VII ) :
wherein R5 i~ as defined hereabove; or an aldehyde of the for~nula:

R5 C~
"H
( VIII ) _7_ ~351~53 or an addition product thereof with an alkali metal hydrogen sulfite.
When the cyclizing agent is an aldehyde there may be added to the reaction mixture an appropriate oxidizing agent such as, for example, nitrobenzene, mercuric oxide, Cu(II) and Pb(II) salts or other suitable oxidants as known in the art, or the aldehyde itself, when added in exc:ess may serve as an oxidant.

Gompounds of formula ( I ) wherein A stands for l-(lower alkyl) -N--C- are also conveniently prepared starting from a corresponding compound (I ) wherein A stands fo~ -NH-CS- by stan-dard S-alkylating procedures, e. g., by the reaction of the thione with an appropriate halolower alkane in an appropriate organic solvent such as, for example, a lower alkanol, e. g., ethanol, propanol, 2-propanol, butanol and the like.

' A nu~nber of the intermediates of formula ( II ) are knowr compounds asld they rnay all be prepared following ~nethodologies which are k~own per se. Depending on the nature of Al in said inte~-mediates ( II ) the following procedures may be utilized for preparing 'chem.

Interrnediates of the for~nula ( II-a ) O '':
H~1-(CH2 )n~W
G' ~
R/~R 2 ( II-a ) may be prepared as follows.

An appropriately substituted 2-chloronitrobenzene of ~ormula ( IX ) is ~eacted with an appropriate aminoalkanol of formula ( X ) by - refluxing the reactants together in an appropriate reaction-inert organic solvent such as, for example, a lower alkanol, preferably butanol, whéreupon there is obtained a ~2-nitrophenyl)amino7alkanol of formula ( XI ), which in turn is subjected to a nitro-to-amine reduction, e. g., by catalytic hydrogenation using an appropriate catalyst such as, for example, Raney-nickel or palladiu~n-on-charcoal. The thus obtained a~-aminophenyl)amino~alkanol of formula ( XII ) is subsequently trans-formed into a 1, 3-dihydro-1-(hydroxyalXyl)-2H-benzimidazol-2-one ( XIII ) by the reaction of ( XII ) with an alkali metal cyanate in aqueous medium or by ~tirring and heating ( XII ) with urea. The desired reactive esters of formula ( II-a) are then easily obtained by converting the hydro~yl group of ( XIII ) into a reactive ester group by the application of generally known methodologies. Halides are conveniently prepared by the reaction of ( XIII ) with an appropriate halogenating agent such as, for example, sul4inyl chloride9 sulfuryl chloride, phosphor penta-chloride, phDsphor pentabromide, phoshoryl chloride and $he like. -When the reacti~re ester is an iodide it is preferably prepared from the corresponding chloride or bromide by the replacement of that halogen with iodine. Other reactive esters such as methanesulfonates and 4-methylbenzenesulfonates are obtained byr the reaction of the alcohol with an appropriate sulfonyl halide such as, for exan~ple, methane-~ulfonyl chloride and 4-~nethylbenzenesulfonyl chloride respectiYely.

The foregoing reactions are more clearly illustrated in the ollowing schematic representation:

o2N ~C1 H2N-(CH2)n-OH ~ ~ 3 R R
~X) (~) ;

ii3 02N~ ( CH2 )n OH . _ >

Ra-Ni Rl R2 ( XI ) H2N NH~(CH2)n~H . -KOCN or R 1 R2 H2N-CO_NH2 (XII) O
HNJ~I-(CH2)n-OH , reacti~e ester > (II-a) ~:
/~/\ 2 formation :
R R
( XIII ) The intermediates ( II-a ) may alternatively be prepared by:

i) reacting an appropriately substituted 1, 3-dihydro-2H-benzimida-zol-2-one of formula (XIV ) wherein P~ , pC2 and the protecting g~oup P are as previously defined, with a haloallcanol of formula ( XV ) following common N-alkylating procedures to obtain an intermediate of formula (XVI);
. .

-10- , i853 ii) converting the hydroxyl function of ( XVI ) into a reactive ester group in the usual manner as previously described; and iii) eliminating the protecting group P of the thus obtained interme-diate of formula (XVII ) following the same procedures as des-cribed hereinbefore for the preparation of the compounds ( I-b ) starting from ( IV ).

The introduction of the hydroxyaL~cyl chain in ( XIV ) to obtain ( XVI ) may also be performed by the reaction of ( ~IV ) with an appro-priate 2-(haloallcyloxy)tetrahydro-2H-pyran, yielding as an interme-diate the corresponding tetrahydro-2H-pyran-2-yl ether derivative of ( XVI ), the ether function of which is hydrolytically split open, e . g ., by the treatment with an aqueous hydrochloric acid solution.

When the reacti~ve ester (II-a) is a chloride, (II-a-l )J it may alternatively be obtained by the reaction of ( XIV ) with a bromochloro-a~ane of formula (XVIII), yielding a l-(chloroalkyl)-1,3-dihydro-3-P-2H-benzirnidazol-2-one of formula (XVII-a ), the prc~tectirlg group of which is subsequently removed in the usual manner to yield the desired chloride (II-a-l ). When in the preparation of the intermediates of formula (XVI), the hydroxyaL~cyl chain to be introduced is hydroxy-2û ethyl, the corresponding ( XVI ) may equally well be prepared by the reaction of (XIV ) with oxirane in the presence of an appropriate strong metal base such as , e. g., sodium n~ethanolate.

The foregoing reactions are illustrated by the foIlowing schematic representation:

~3~ 3~

.
P-N NH

R~2 ( XIV ) - hal~(CH2)n~H / \ Br-(CH2)n~Cl :
(XV ) ~ \~ (XVIII ) P-N~-(CH2) -OH . P-N N~(CH2)n~

R~\R 2 R~ R 2 ( XVI ) ~ XVII-a ) ¦ reaotil~re ester formation elimination of ~ P

P ~~(CHz)n-w ~ 1 2)n R2 Rl R2 (XVII) (II-a-l ) ¦ elimination of P
V
(II-a) ~, .

5~ .

Intermediates of the fo:rmula (II-b) Ll , N~ ~ (CH2 )n ~W

( II-b ) wherein Rl, R2, Ll, n and W are a~ previously defined are convenient-ly obtained by the introduction of the reactive ester side chain into a star$ing material of the formula ( XIX ) Ll ~
~ ` .
N NH

Rl R2 (XIX) `' The introduction of the (ZH2) -W group may be performed follo-wing similar procedures to th~se described hereinbefore for the intrcduction of said group into starting materials of forrnula ( XIV ).

The intermediates of formula ~ II-b ) may also be prepared by ~ubjecting an appropriate hydroxyalkyl substituted be~zenediamine of ormula (XII) to ring closure with an appropriate cyclizing agent as described hereinabove, followed b~ the con~rersion o the hydroxyl group of the thus obtained intermediate of formula ( XX ) into a reactive ester group.

( XII ) cyclization > N~N-(CH2)n-OH
' .

/1~ 2 reactive ester formation ' ( II-b ) Irltermediates c>f formula ( II-c ) S~(lower alkyl) ~ 2 n R~R 2 ( II-c ) are conveniently obtained by first cyclizing an appropriate intermediate : .
of formula ( XII ) with thiourea to obtain a 1, 3-dihydro-2H-benzimidazol-2-thione of folomula ( XXI ), S-alkylating the latter with an appropriate halo(lower alkane) in the usual manner and, finally, converting the hydroxyl group of the thus obtained (XXII ) into a reactive ester group a~ previously defined.

S S ~(CH2ln~H S-alkylatio~

R/~ R
( XXI ) 35~3~3 S-(lower alkyl) N~N-(cH2)noH reactive ester ( II-c ) ~ formation R~\R 2 ( XXII ) .

Intermediates of the formula (III ) wherein Q standæ for ~C=O (III-a ), are generally known and rnay be prspared following art-known procedures. Those intermediates of formula ( III ) wherein Q stands for ~C(OR )2' (III-b),or ~C~ , (III-c ),can easily (CH2ym be derived from ( III-a ) by first N-acylating said (III-a) in the usual , -~
manner with an appropriate acyl halide, e. g., acetyl chloride, there-after ~ubjecting the thus obtained ( XXIII ) to a ketalization reaction with an appropriate lower allcanol ( XXIV ) or alkanediol ( XXV ) to obtain a --ketale of respectively formula ( XXVI-a ) or ( XXVI-b ), fro~n which the desired intermediates (III-b ) ancL (III-c ) are easily obtained after hydrolytically splitting of the protecting acyl group in aLkaline medium.
The aforementio~ed ketalization reaction i~ conveniently carried out by stirring and re1uxing the reactants together under azeotropic water removal in an appropriate organic solvent, preferably an aromatic 1~ hydrocarbon such as benzene, methylbenzene, dimethylbenzene and the like, in 1:he presence of an appropriate strong acid, preferably 4-methyl-benzenesulfonic acid.
.
The foregoing reactions are illustrated hereaf~er:

Acyl halide ~ ~N~

( III-a ) ( XXIII ) .
' --~ ~5~353 ~, :

~CYI-~C~ ~ ( Ill-b ) R OH /benzene ( XXVI-a ) ( XXIV ) /4 -methylbenz ene -/ suLfonic acid ( XXIII ) \ benzene \ 4_methylbenzene-\ sulfonic acid H~(CH2)m H\

(XXV ) \ R `~
\~ ~cyl-~C~ --j ( III-c ) (CH2 )m ( XXVI-b ) The intermediates of for~nula ( IV ) may be obtained by the c~ndensation of a reactive ester of formula ( XVII ) with an intermediate `
of formula ~ III ) wherein Q stands for ~ C =O. .
The intermediates of formula (V ) are obtained by the con-S densation of an appropriate reactive ester of formula ( XXVII ) with a piperidine derivative of formula ( III ) followed by the reduction of the nitro group of the thus obtained intermediate ( XXVIII ) to an amino group according to standard nitro-to-amine reduction procedures, e. g., by the reaction of the nitro compound with nascent hydrogen or by cata- -lytic hydrogenation in the presence of an appropriate catalyst such as, for example, Raney-nickel.

,- , 16- .

.

~6~ 3 02N NH-(CH2)n_W

~\ , Rl R2 ( XXVII ) R
, .
02N NH-(CH2)n_N~, }Q~
nitro-to-amine (V ) reduction Rl R2 ( XXVIII ) . .
The reactive esters of formula ( XXVII ), used as starting ` materials herein, are easily prepared starting from an alcohol of ~ormula ( XI ) by the conversion of the hydroxyl function thereof into a reactive ester group following. standard pr~cedures as previously described herein, The compounds of the ~ormulas ( IV ) and ( V ) are deemed to be novel and as useful intermediates in the preparation of the pharma ceutically useful compounds of formula ( I ) they constitute an additional ~:
feature of this invention.

The ultimate starting materials in each of the foregoing ~ .
preparations are generally known and they may all be prepared following known methodologies as described in the li~erature.

. .

-17- .

~85~3 The compounds of this invention may be converted to their therapeutically useful acid addition salts by treatment with an appropriate acid, such as, for example, an inorganic acid, such as, hydrohalic acid, e. g., hydrochloric, hydrobromic and the like, and sulfuric acid, nitric acid, phosphoric acid and the like; or an organic acid, such as, for example, acetic, propanoic, 2-hydroxyacetic, 2 -hydroxypropanoic, 2 -oxopropanoic, propanedioic, butanedioic, ..
(Z)-2-butenedioic, (E)-2-butenedioic, 2-hydroxybutanedioic, 2, 3-dihydroxybutanedioic, 2-hydroxy-1, 2, 3-propanetricarboxylic, benzoic,

3-phenyl-2-propenoic, a-hydroxybenzeneacetic, methanesulfonic, ethanesulfonic, benzenesulfonic, 4-methylben7.enesulfonic, cyclo-hexanesulfamic, 2-hydroxyberlzoic, 4-amino 2-hydroxybenzoic and the like acids.
Conversely the salt form can be con~rerted by treatment with alkali into the free base form.

~ 5853 The cornpounds of formula ( I ) and the ~herapeutically active acid addition salts thereof possess strong neuroleptic activity. Such neuroleptic activity is evidenced by the experimental data obtained in at least one of two different test procedures, viz., the comb ned apo-morphine-tryptamine_ and norepinephrine test in rats, and the apomorphine test in dogs. The tests were carried out following the procedures described hereafter and the experimental data which were obtained are summarized in the tables I, IIandIII. Thecon~poundslistedtherein are not given for the purpose of limiting the invention thereto but _ 10 only in order to exemplify the useful neuroleptic propert;es of all the compounds within the scope of formula ( I ~.

I .
A) The combined apoInorphine-tryptamine- and norepinephrine test in rats, .
The experimental animals used in this test were adult male Wistar rats (weight 240 + lOg). After an ove~night fast, the animals were treated subcutaneously (1 ml/lOOg) with an aqueous solution of the compound under investigation ( time = zero) and put ;n isolated obser~ration cages. Thirty minutes thereafter (time = 30 minutes) 1. 2S mg/kg oI apomorphine hydrochloride (APO) was injected intra-venously and the rats were observed over a 1 hour period for the pre~ence or absence of the following apomorphine-induced phenomena:
agitation and stereotypic chewing. At the end of this 1 hour period (time ~ 9û ~ninutes) the same animals were ii~jected intravenously with 40 mg/kg of tryptamine (TRY) and the presence of the typical tryptamine-induced bilateral tonic seizures was noted. T-vo hours a~er pretreatment (time = 120 minutes) finaliy, the same animals were challenged with l . 25 mg/kg intravenously of norephinephrine (NOR) and possible mortality was looked for up to 60 rninutes later.
.
.

-19- ~

,3 Table I andII give the lowest effective dose (LED ) ie., the dose level the efect of which was statistically significantly different from that observed in the corresponding untreated controls (Fisher exact probability test), for each o the th~ee agonists studied (APO, TRY and NOR in the table).

.
B) The apomorphine test in dogs.
. .
Neuroleptic drugs are known to inhibit emesis induced by apomorphine in dogs. The compounds listed in tablelITwere .
. administered either subcutaneously or orally to a minimum of a group of three beagle dogs. The animals were challenged 1, 4 or .. 16 hours after subcutaneous administration or 4 hours after oral administration with a standard dose of 0O 31 mg/kg apomor~hine .
hydrochlorid.e (subcutaneously), This high dose of apomorphine induces emesis in all untreated control dogs.
Table III gi~es the PD50-~ralues (in mg/kg subcutaneously or orally), io e~, the dose of the compound protecting at the stated time half of the animals from emesisO

.

.
.. , i .
.

~35~
Table I: Antiapomorphine (APO)-, antitryptamine (TRY)- and anti-norepinephrine (NORl activity of the listed compounds in rats.

HN - (CH2)n-N ~ R

t~ ' 1 LED (APO) LED(TRY) TEn(NoR) Compound n R R R in Mg/kg s.c. in mg/kg s.c. in mg/kg s.c.
. . ~
A 2 H H 4-F 10 0.16 2.5 B 3 H H 4-F 0.04 0.08 2.5 C 3 5-Cl H 4-F 0.08 0.16 5 D 3 H 6-Cl 4-F 0.31 0.08 5 E 3 H 7-Cl 4-F 1.25 1.25 2.5 F 3 5-C1 6-Cl 4-F 1.25 2.5 > 10 :~
G 35-CH3 H 4-F 0.02 0.08 1.25 H 35-CF3 H 4-F 0.31 5 > 10 I 35-CH3 6-CH3 4-F 0.63 2.5 5 J 4 H H 4-F 2.5 0.31 0.31 :-K 3 H H 4-Cl 2.5 5 5 L 3 H 6- ~ 4-F 0.31 0.63 10 ~L~8~

~.
_ ~
~ ` ~, ... . .
_ ~ o ~ . I
~.,, 0 .
D~
.

~ o ~.,, ~ ~ ~J :
~ , ô ~
~ o o oS
.
. . . I
~z C~ ~ ~,~o=~o=~ , ~
.` ~ .
a) .~ ~ , . .
.,, .
~ .,, 0 Q~

N

H( ~ ~ ,~ ~ I
Q~1~
! :

~o ~i3 ~__ ~, ~ In ~r , Z ~ ~, I o .,, ~, ' ~ ' ,_ ~ ~r ~.Y o In o ~ o ' ..
U , .. ':
O ~ ~ ~ `~D l' '`.;
~ ~: o ~,.......... . ..
~ ~ o o o , '.
a ~rl ' .
- ' :

o=~ 1~\o~ =~
' ~' .
. ' ' U ( ~ ~z~3 ~u ~<~

H L~ ~

~13S135i3 U ~, la~ N
W ~
.,1 . _ _ ~1 ':~ l E~ . ,, ,~rl '~

X U~ ,~

_ __ ~, 0~, =C' ~ ~ ~ ~ ~ ' _~ ._ ._ .. .__ .. _ __ .
~ ~ . ' ~( ~ C~c, ~ X~z~ ~ZX~, :
~ _ _ . ,.
'.' ~3 :
~ u~
C~ _ . _ _ .

- 23a - ~

~5~353 Table III. Antiapomorphine activity of the listed corrpounds in dogs, . _ , . . . ~ .
Antiapornorphine effect in clogs: PD50-values in mg/kg sub-Compound cutaneouslsr or orally at the stated time.
Ater 1 ho~lrAfter 4 hours After 4 hours After 16 hoursl (subcut, )(subcut. )(orally) (subcut. ) .
A ~ 1.5 _ B 0, 06 . 0. 40 . _ C 0.008 0.015 0.015 0.06 D 0. 1 0 _ _ _ E 0 . 25 _ _ F 0.03 0,018 0.06 0.12 : 0, 0040. 008 0 . 0 1 5 0 . 1 2 H 0. 20 0. 1 2 _ _ . . .
I 0. 01 50. 0 1 5 0. 07 _ . J 0,~ _ ~ _ K 0. 10 _ _ _ L 0.03 0.05 0.12 _ s M 0. 63 _ _ _ N 0 . 45 _ _ _ O 0.50 0.63 - _ - _ P 0. 01 ~0. 025 0. 1 0 _ Q 0.10 0.03 0.03 0.06 ':
R . 63 _ _ _ . - ::
S . _ . 0.25 _ T 0 . 50 _ 0 . 1 6 _ _ __. 0. 80 1. 0 _ - . -' ~24 -~31358~i3 The following examples are intended to illustrate and not to limit the invention thereto. Unless otherwise stated all parts therein are by weight.

Exarnple I

I
A mixture of 100 parts of 1,2-dichloro-3-nitrobenzene, 95 parts of 3-amino-l~propanol and 200 parts of butanol is stirred and refluxed overnight. The reaction mixture is cooled and evaporated.
The residue is talcen up in water and the product is extracted with methylben~ne. The extract is washed with water9 dried, filtered and evaporated, yielding 115 parts of 3-~2-chloro-6-nitrophenyl)amino7-l-propanol as a residue.
'.. ,., , ' , , `
' . , ,. 1:

: 1.
-- Example II ` ~J -Following the procedure of Example I and using equi~alent amount~ of the appropriate startîng materials there -are prepared:

3-~4, 5-dichl~ro-2-nitrophenyl)amin~7-1 -p~opanol; mp. 97C; , , 3_~4-methyl_2-nitrophenyl)aminoJ-l-propanol as a residue; and 3-~-nitro-4-(tri1uoromethyl)pheny~7amino ~-1-propanol. ,-' ' 5~ii3 . ' .
.
Example III
. ;
A mixture of 7û parts of 3-~4-methyl-Z-nitrophenyl)amino7-l-propanol and 400 parts of methallol is hydrogenated at normal pressure and at room temperature with lO parts of palladium-on-charcoal catalyst 10%. After the calculated amount of hydrogen is taken up, the catalyst , -is iltered off and the filtrate is evaporated, yieiding 54 parts (91 %) of 3-~-amino-4-methylphenyl)amino7-1-propanol as a residue. -- - ;
. . , , , Exampl~ IV
..... . _ .. . . .
A mixture of 39. 7 parts of 3-~4, 5-dichloro-2-nitrophenyl)-amin~ propanol and 400 parts of methanol is hydrogenated at norm21 pressure and at room temperature with 5 parts of Raney-nickel catalyst. ~- ~
Ater the calculated amoun~ o~ hydrogen is taken up, the catalyst is - i ~
filtered off. The filtrate is acidified with 24 parts of a hydrochlo~lc acid solutior~ while stirring. The solvent is evaporated and the solid r~:sidue ifi stirred in 2-propanol. The product is filtered off and dried ! ~ '^
in vacuo, yielding 31; 5 part~ of 3-~2-amino-4, 5-dichlorophenyl)amino7-l-propanol hydrochloride; mp. ~ 185C.

.~
'' '` ' ' ' ' ' ~
, '~, ~515 53 ., :, Exam~e V
'~
Follo~ing the procedure of Example IV the following 3-/r2-aminophenyl)amino7-1-propanols are prepared by hydrogen~
ating the corresponding 3-~2-nitrophenyl)amino7propanols: -, 3-a2-amino-4-chlorophenyl)amino~ propanol aæ an oily re~idue; ;-3-~2-amino-6-chlorophenyl)amino7-1-propanol as a re6idue; and 3~ amino-4-(trifluoromethyl)phenyl7a~nino}-1-propanol.
.

.
Example VI
;, A mi~:ture of 20 parts of Z~2-amino-5-chlorophenyl)-anlin~7ethanol arld 18 parts of urea is stirred and hcatcd for 4 hours in an oil-bath a~ about 190Co The reac~ion mixture is cooled and dis~olved in alkaline water. The solution is acidified ~vith a concen- i;
trated hydrochloxic acid soluLion. The prccipitated product i8 .''~
~iltered off, washed with water and dried, yielding 13 parts (57,1%) of 6-chloro-1,3-dihydro-l-(2-hydroxyethyl)-2I~benz- ,;
imidazol-~2-one; mp. 160C. ,:

.
', , , `' ~

, - - !

~5~3~3 Example ~II
- i , Following the procedure of ExalnpleVI there is prepared:

5 -chloro -1 -(2 -hydroxyethyl) - 1, 3 -dihydro -2H -benzimidazol-2 -one;
mp. 1 76 -1 78 . 2 C by the reaction of 2 -,~2 -amino -4 - chlorophenyl) -amino7-ethanol with urea.
.,-' ' 'i'.' ExamPle VIII
.. . , . . .... . ........ .. . . . ..... ..... . . ,.. . ~ , To a stirred mixture of 31. 2- parts of 3-~2-amino-4, 5-di-chlorophenyl)amino7-1-propanol hydrochloride in 200 parts o water is added dropwise-, dusing a 15 minutes-period, a solution of 10. 6 parts '~
of potassium cyanate in 50 parts of water at a temperature between 15 and ZO~C. Upon completion, stirring i.s continued irst for 20 minutes at room temperature and further for 20 hours at re1ux. The i .
reaction mixture is allowed to cool over week-end to room temperature.
The precipitated product is filtered of and boiled in trichloromethane. -The undissolved part is filtered of f and boiled in 4-methyl-2-pentanone.
After cooling, the product i6 filtered off and dried, yielding 14. ~ part~
(48 %)- o 5, 6-dichloro-1, 3-dihydro-1 -(3-hydsoxypropyl)-2H-benzimida-æol-2 one; mp. 174.7C~
. .

. ' , .

.

8~3 . ~-Example IX
- ' '' ,.

;:
Following the prc>cedure of Example VIII the following 1, 3_ dihydro-1-(3-hydroxypropyl)-2H-benzimidazol-Z-ones are prepared starting from the appropriate 3-~2-arninophenyl)amino7-1-propanols:

5-chloro-1, 3-dihydro 1-(3-hydroxypropyl)-2H-benzimidazol-2-one;
mp. 148. 8C, . .

1, 3-dihydro-1-(3-hydroxypropyl)-5-methyl-2H-benzimidazol-2-one; ' mp. 114 . 1 C .

. ,, _, , .

4-chloro~l, 3-dihydro 3-(3-hydroxypropyl)-2~-benzimidazol-2-one; and 1, 3-dihydro-1-(3-hydroxypropyl)-5-(trinuo:romethyl)-2~-benzimidazol- 1' ,"
2-one. . - -Example X . . ~ .

To a stirred and refluxing (water-separator) mixture of 30 parts '. ;
of 3-R--2-amino-4-chlorophenyl)amin~ propanol and 0.1 parts of 4-n~ethylbenzenesulfonio acid in 405 parts of methylbenzene is added dropwi~e a solution of 34 parts of cyclohexanecarboxaldehyde in 4 parts of methylbenzene. Upon completion, stirring is continued for .
1 hour at reflux temperature wlth water-separator. The methyl~
benzene is removed by evaporation in vacuo and the residue is triturated in 2,~2~-oxybispropane. The product is fil~ered of and dried, yielding - .;
16. 5 pa:rts (38 %) of 5-chloro-2 -cyclohexyl-lH-benzimidazole~l -propa- - ;:
~ol; mLp. 95 C .
''': :, Example XI
A mlxture of 40 parts of 3-¢2-amino-5-chlorophenyl)amino~^
l-propanol, 87 parts of sodium a-hydroxycyclohexanemethanesulronate and 200 parts of ethanol is stirred and re~iuxed for lO minutes. The reaction mixture is diluted with water and the sol~ellt is evaporated.
The residue is extracted a few times with trichloromethane. The com-bined extracts are dried, filtered and evaporated. The oily residue is triturated in 2, 2 ' -oxybispropane: a st;cky tar precipitate s . The 2, 2 ' -oxybispropane is decanted and upon stirring at room temperature, the product is allowed to precipitate. It is filtered off and dried, yielding 34 parts (585~) of 6-chloro-2-cyclohexyl-lH-benzimidazole-l-propanol;
mp. l Z û . 1 C . ;

. ~

Example XII -Following the procedure of Example XI there is -prepared 5-chloro-2-(phenylmethyl~-lH-benzimidazole-l-propanol as a residue, by the reaction of 3-~!r2-amino-4- -chlorophenyl)arnino7-l-p~opanol with sodium cc-hydroxybenzene-ethan e sulfonate .

Example XIII
A mixture of 30 parts of lH-benzimidazole, 49 parts of 2-(4-chlorobutoxy)tetrahydro-2H-pyran, 21 parts of potassium hydroxide and 200 paIts of ethanol is stirred and reflu~:ed over~ight. The reaction mixture is cooled to roo~i temperature, filtered and the filtrate is evaporated. The residue is stirred in water and acidified with a dilutod hydrochloric acid solution. The whole is stirred and heated for 30 rninutes in a water-bath. After cooling to roon~ tennperature, the pro-duct is extracted with methylbenzene. The aqueous phase is separated and alkalized with ammonium hydroxide. The product is extracted with dichloromethane. The extract is dried, filtered and evaporated, yielding 50 parts of lH-benzimidazole-l-butanolas an oily residue.
~ 31 --, ,., ,, ~, . , ~358~3 Example XIV
... .... .
To' a stirred mi~ture of 37. 6 parts of 1, 3-dih~dro-6-methyl-1-(l-methylethellyl)-2H-benzimidazol-2-one, 2 parts o sodium methoxide solution 30% and 320 parts of absolute ethanol is added a solution oI 22 parts of oxirane in 40 par~s of absolute ethanol, Stirring is continued ~irst overnight at room temperature and urther ~or 3 hours at reIlw;~ The ethanol is evaporated, yielding ~6 part's (100%) o 1, 3-dihydro-1_(2-hydroxyethyl)_5_methyi-3-(1-methyl-ethenyl)-2H-benzimidazol-2-one as an oily residue.
. . - , . ' , :
:., To a- stirred solution of 46 parts of 1, 3-dihydro-1 -(2-hydroxy-ethyl)-5-methyl-3~(l-methylcthenyl)-2H-benzimidazol-2-one in 168 parts o cthanol are added 48 parts of hydrochloric acid solution and the whole is stirred for 2 hours at rbom temperature, The reaction mixture is evaporated and the residue is stirred in 250 parts of water, The precipitated product is filtered off! washed with 2, 2'-oxybis- :~
psopane and dried, yielding 22~3 parts (58%) of 1,3-dihydro-1- ~;
(2~hydroxyethyl)-5-meth~ 2H-benzimidazol-2-one; mp. 158. 7C.
.
. - ' , ' - ~
Example XV
, To a stirred'mixture of 22. 6 parts of 6-chloro-1, 3-dihydro-1- _ (3-hydroxypropyl)-2H-benzimidazol-2-one and 300 parts of trichloro-'methane are added dropwise 32 parts of sulfinyl chloride. Upon comple-tion, stirring is continued for 3 hours at reflux. After st~rring with activated charcoal, the reaction mixture is filtered hot over hyflo. The' filtràte is evaporated and the residue is disso~ved in methylbenzene.
The solution is washed a few times with water, dried, filtered and eYa-porated. The oily residue is trituTated in 2, 2'-oxybispropane. The solid product is filtered off and dried, yielding 19 parts (77.5%) of '6~chloro-1-(3-chloropropyl)-1, 3-dihydro-2H-benzimidazol-2-one;
mp 122C.
.
. -- 32 ~

~L~85853 Exarnple XVI
.
- Following the procedure of Example XV the ollowing chloroallcyl benzimidazoles are prepared starting from the cor-responding hydroxy compounds: .

5-chloro-1-~2-chloroethyl)-1, 3-dihydro-2H-benzimidazol-2-one;
mp. 173. 4-C; . . .

6-chloro-1 -(2-chloroethyl)-1, 3-dihydro-2H-benzimidazol-2-one; `.
mp. 164C;

1-(2-chloroethyl)-1, 3-dihydro-5-methyl-2H-benzimidazol-~-one;
mp. 120C; . . ........

1-(3-chloropropyl)-1, 3-dihydro-5-(trifluoromethyl)-2H~benzimidazol- .
2-one; . ~

1-(4-chlorobutyl)-lH-benzimidazole as an oily residue; -5-chloro-1-(3-chloropropyl)-2-cyclohexyl-lH-benzimidazole hydro-chloride; mp. 21 1 . 7 C; -6-t:hloro-1-(3-chloropropyl)-2-cyclohexyl-lH-benzimidazole hydro-chloride; mp. 227. 5C;

1-(3-chloropropyl)-2-(phenylmethyl)-lH-benzimidazole; mp. 112~C;
and . ~ .

5-chloro-1-(3-chloropropyl)-2-(phenylmethyl)-lH-benzimidazole as a solid residue.

~ 33~ ~:-' .

~ 5~353 . .
_xample XVII
.
To stirred n~ixture of 12. 6 parts of 1, 3-dihydro-1-(2-hydroxy-ethyl3-2H-benzimi~azol-2-one, 10.1 parts o~N,N-diethylethan-amine and 195 parts of dichloromct11ane is added dropwise a solu~ion of 9,2 parts of lnethanesulfonyl chloride in 13 parts of dichloxo-methane: exothermic reaction. Upon cor~pletion, stirring is continued ~-for 1 hour at re~lux temperature, The reaction mixture is cooled :-and poured onto water. The precipil:ated product is filtered off, washed ~ith 2, 2'-oxybispropane and crystallized from 4-n~ethyl-2-pentanone (activated charcoal), yielding, after drying, 7. 5 parts o~ 2, 3-d;hydro-2-oxo-lH-benz~imidazol-l-yl)ethyl mcthanesul~onate;
mp. 1560 7C.
-Example XV'III

Following the procedure of Example XVII the following methanesulfonates are derived from bhe corresponding alcohol~: :

3 -(2, 3 -dihydro -5 -methyl -2 -oxo -1 H-benzimiclazc>l -1 -yl)propyl _ methanesulfonate; mp. 125C;
3 -(5 -chloro-2, 3 -dihydro-2 -oxo- lH -benzimidazol- 1 -yl)propyl nethanesul~onate; mp. + 140C; :
. .
3-(7-chloro-2, 3-dihydro-2-oxo-lH-benzimidazol-l-yl)propyl n~ethane- - .
~ulfonate; and , - 3-(5, 6-dichloro-2, 3-dihydro-2-oxo-lH-benzimidazol-l yl)propyl .
methanesulfonate as an oily residue.

-- 3q --.

; ~
. I

.' ! . . - , , .
Example XIX
, . . . .
To a stirxed and hot ( '- 50C) mixture of 34 parts of 1, 3 dihydro-5-methyl-l~ methylethenyl).-2H-benzimidazol-2-one, 5 parts of N, N, N-triethylbenzenemethanaminium chloride and 300 parts of sodium hydroxide solution 50% are added 57 parts of 1--brcsmo-3-cl1loropropane (exothermic reaction: temperature rises to 70C). The whole is stirred for 1 hour at 65-70C. The reaction mixture is cooled and poured onto crushed ice. The product is extracted ,-with methylbenzene. The extract is washed three times with water, dried, filtered and evaporated. The oily residue is distilled, yielding 40 parts (84%3 of 3-(3-chloropropyl)-1, 3-dihydro-5-methyl- '`
l-(l-lnethylethenyl)-2H-benzimidazol-2-one; bpo 140 C at 0. 02 mnl. ?
pressure.
. ~
- , .
.
, . ' ', Example XX -- , , ~ ,~
Following the procedure of Example XIX and using -equivalent amounts of the appropriate ~tarting materials there are prepared:
. .
1 -(4-chlorobutyl)-1, 3-dihydro-3-(1 -methyl-2-phenylethenyl)-2H- ' benzimidazol-2-one aB a residue; , ;-1-t3-chloropropyl)-1, 3-dihydro-5, 6-dimethyl-3-(1-methyl-2-pheny1ethenyl~-2H-benzimidazol-2-one; mp 98C; and -, 1-(3-chloropropyl)-2-cyclohe~yl-lH-benzimidazole as an oily residue.

.

i3 . .

xample XXI
A mixture of 52, 5 parts of 1~ chlorobutyl)-l, 3-dihydro- i 3~ methyl-2-phenylet1lenyl)-2H-benzimidazol-2-one, 220 part6 !
of hydrochloric acid solution 6N and 240 parts of ethanol is stirred and reIluxed for 6 hours, The reaction mLxture is evaporated and the residue is dissolved in trichloromethane, The solution is dricd, "i iltered and evapo~ated. The residue is crystallized from 2, 2'-oxy-bispropane, yielding, after drying, 25 parts (72.5%) o 1--(4- 7 chlorobutyl)-l, 3-dihydro-2~-benzi~nidazol-2-one; mp, 90C.

. .
- . . : .
Exanlple XXII - ~ ~
, .
Following the procedure of Example XXI there is prepared 1-(3-chloropropyl)-1, 3-dihydro-5, 6-dimethyl-2H-benzimidazol-2-one; mp. 140C, starting from the correR-ponding ~l-methyl-2-phenylethenyl)-~ul~stitute~ compound. ~
. . i' ' , : . ',.' Example XXIII
To a stixred solution of 8. 5 parts of 1, 3-dihydro-1-(l-methyl-e1henyl)-2H-benzimidazol-2-one in 45 parts o N, N-dilnethylIo~lnarnide are added portionwise l. 7 parts of sodium hydride dispersion 78%. ~ t Atcr stirring ~or 1 hour at Toom temperature, the whole is coolFd to ~
0-5~C and 8. 65 parts of 1-bromo-3-chlorop~opane are added dropwise (slowly). IJpon completion, stirring is continued for 3 hours at room ,-temperature, The reaction mixture is poured onto crushed ice and the product is extracted with methylbenzene. The extract is ~vashed with water, dried, ~iltered and evaporated. The residue is . rystallized ~rom 2-propanol, yielding 5. 5 paxl:s(44%) of 1-(3-chloropropyl)-1, 3 dihydro-3 (1-methylethenyl)-2H-benzimidazol-2-one; mp. 115C.

, ....

!

Example XXIV
A mixture of 8. 2 parts of 2-(methylthio)-lH-benzimidazole, 16 parts of 1-bromo-3-chloropropane, 5. 3 parts of sodium carbonate and 200 parts of 4-methyl-2-pentanone is stirred and refluxed for 44 hourR. After cooling, water is added and the layers are separated The organic phase is dried, filtered and evaporated. The residue is stirred in Z,2'-oxybispropane. The unreacted starting material i~
filtered off and the filtrate is evaporated, yielding 6 parts (50%) of 1 -(3-chloropropyl)-Z -(methylthio)-lH-benzimidazole as an oily residue.
, . ., , , Example XXV
, ............................. -- ' To a stirred mixture of 39. 2 parts of 3-(2-nitrophenyl)amino-l-propanol and 225 parts of trichloromethane are added dropwise `
35. 7 parts o~ sulfinyl chlc~ride (exothermic reaction: temperature rises to 45C). Upon completion, stirring is continued for 6 hours at refl~
temperature. The reaction mixture is evaporated, yielding 43 parts (100%) of N-(3-chlc>ropropyl)-2-nitrobenzenamine as a residue.

A mixture of 26 . 6 parts of N-(3 -chloropropyl) -2 -nitroben~en amine, 24. 35 parts of (4-fluorophenyl)(4-piperidinyl)methanone hydro-chloride, 21. 2 parts of sodium carbonate, 0. 2 parts of potassium iodi- ;
de and 2û0 parts of 4-methyl-2-pentanone is stirred and refluxed for 24 hours with water-separator. The reaction mixture is cooled, water is added and the layers are separated. The organic phase i~ dried, filteaed and evaporated, yielding 27 parts (70%) OI (4~fluoropnenyl) 3_~2-nitrophenyl)aminoJpropyl¦-4_piperidiny~7methanone as a r esidue. ~ , , _ ...... - --- :
,' , ' ' '.
-37- . ~

. ' ' . '~.;
.
. ~ '~

8~3 A mixture of 27 parts of (4-fluorophenyl) ~- {3-a2-nitrophenyl)-~mino~propyl~-4-piperidinyl_7methanone in ~00 paxts of n~ethanol is hydrogenated at normal pressure and at room temperature with 5 parts of Raney-nickel catalyst. After the calculated amount of hydrogen i8 ' ' taken up, the catalyst is filtered off over hyflo and the filtrate is eva-porated, yielding 25 parts (lOO~o) of ~ 3-~-aminophenyl)amino7-propyl }-4-piperidiny~7 (4-fluorophenyl)methanone as a residue. . -- ' : ' - :;
'. ' ' ~ ' ',~`', Example XXVI
' , ' ' ' , , '. ','', A mixture of 5. 3 parts of 3-(3-chloropropyl)-1, 3-dihydro-5- j methyl-l-(l-me'chylethenyl)-2H-benzimidazol-2-one, 4, 9 parts of (4-fluorophenyl)(4-piperidinyl)methanone hydrochloride, B. 5 parts of sodium carbonate, 0. 2 parts of potassium iodide and 200 part~ ! -o~ 4-methyl-2-pentanone is st;rred and refluxed overnight with water-separator. The reaction mi~Yture is cooled, water is added and the layers are separated. The 4-methyl-2-pentanone phase is dried, filtered and . ¦ -evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol ~95:5 by volume) as eluent. The pure fractions are collected and the eluent is :
evaporated, yielding 4.5 parts (52~o) Of 3-~3-~-(4-fluoroben~oyl~ .
pipeTIdiny~7propyl}-1, 3-dihydro-5-methyl-1-(1 -methylethenyl)-2H_ ~ .
benzi~nidazol-2-one as an oily residue. ` I
- '' . , . : ' """
-~8- 1 I

.' ''.

.

;i3 Example XXVII
~ A mixture of 74. 7 parts of 1-acetyl-4-C4-fluorophenyl)carbony~
piperidine, 46. 5 parts of 1, 2-ethanediol, 3 parts of 4-methylben~ene-sulfonic acid and 810 parts of benzene is stirred and refluxed for 108 hours with water-separator. The reaction mixture is cooled and washed successively with a mixture of 250 parts of water and 22 5 parts of ammonium hydroxide, and with Z50 parts of water. The organic phase is separated, dried, filtered and evaporated. The residue is puriied by column-chro~atography over silica gel using a mixture of trichloro-methane and 2-propanone (50:50 by volume) as eluent. The pure fractions are collected and the eluent is evaporated, yielding 50 parts (56. 8 %) of 1 -acetyl-4- ~-(4 -~luorophenyl)- 1, 3 - dioxolan -2 -y~7piperidine as a residue.

. ' ' ' ' , ' ~':

A mixture of 5 parts of 1-acetyl-4-,~-(4-fluorophenyl)-1,3- -dioxolan-Z-y~7pipelidine and 100 parts of sodium hydroxide solution 10% is stirred and refluxed overnight. The reaction mixture is cooled and the product is extracted with trichloromethane. The extract is dried, filtered and evaporated. The solid residue is stirred in 2, 2'-oxybispropane. The product is filtered off and dried in vacuo at 40C, yielding 3. 5 parts (82~o) of 4-C-(~-fluorophenyl)-1, 3 dioxolan-2-y~
piperidine. - ;

' , . . ':

..

~1~85~53 Example XXVIII

~ mixture of 5.6 parts of 6-chloro-1-(3-chloro-propyl)-1,3-dihydro-2H-benzimidazol-2-one, 4.9 parts of (4-fluorophenyl) (4-piperidinyl) methanone hydrochloride, 8.5 parts of sodium carbonate, 0.2 parts of potassium iodide and 200 parts of 4-methyl-2-pentanone is stirred and refluxed overnight with water-separator. After cooling, water is added and the layers are separated. The 4-methyl-2-pentanone-phase is dried, filtered and evaporated. The residue is purified by column chromatography over silica gel using a mixture of trichloromethane and 5% of methanol as eluent.
The pure fractions are collected and the eluent is evaporated.
The residue is crystallized from 2-propanol, yielding 1.9 parts (23%) of 6-chloro-1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]
propyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 157C.

Example XXXIX

Eollowing -the procedure of Example XXVIII and using equivalent amounts of the appropriate starting materials, the following compounds are prepared:

1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5-(trifluoromethyl)-2H-benzimidazol-2-one; mp. 160.2C;

1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5, 6-dimethyl-2H-benzimidazol-2-one; mp. 195.3C;

1-{4-~4-(4-fluorobenzoyl)-1-piperidinyl]butyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 176.5C;

~L~858S3 3-{3-[4-(4-fluorobenzoyl)-1-piperidinyl~propyl}-2(3H)-benzoxazolone; mp. 145.2C;

{1-[2-(lH-benzimidazol-l-yl)ethyl]-4-piperidinyl}(4-fluoro-phenyl)methanone; mp. 119.2C;

{1-~3-(lH-benzimidazol-l-yl)propyl]-4-piperidinyl}(4-fluoro-phenyl)methanone; mp. 129.4C;

{1-[4-(lH-benzimidaæol-l-yl)butyl]-4-piperidinyl}(4-fluoro-phenyl)methanone; mp. 112.9C;

{1-[3-(2-cyclohexyl-lH-benzimidazol-l-yl)propyl]-4-piper-idinyl}(4-fluorophenyl)methanone; mp. 105.5C;

{1-[3-(5-chloro-2-cyclohexyl-lH-benzimidazol-l-yl)propyl]-4-piperidinyl}(4-fluorophenyl)methanone; mp. 103.6C;

{l-r3-(6-chloro-2-cyclohexyl-lH-benzimidazol-l-yl)propyl]- 4-piperidinyl}(4-fluorophenyl)methanone; mp. 116.8C;

(4-fluorophenyl) [1-{3-[2-(methylthio)-lH-benzimidazol-l-yl]-propyl~4-piperidinyl]methanone; mp. 112.2C;

~4-fluorophenyl [1-{3-[2-(phenylmethyl)-lH-benzimidazol-l-yl]-propyl}-4-piperidinyl]methanone; mp. 133.3C; and [1-{3-[5-chloro-2-(phenylmethyl)-lH-benzimidazol-l-yl]propyl}
-4-piperidinyl] (4-fluorophenyl)methanone; mp. 95.3C.

Example XXX

A mixture of 5.5 parts of 3-(5-chloro-2,3-dihydro-2-oxo-lH-benzimidazol l-yl)propyl methanesulfonate, 3.6 parts of (4-fluorophenyl) (4-piperidinyl) methanone, 6 parts of sodium carbonate and 80 parts of 4-methyl-2-pentanone is stirred and refluxed overnight. After cooling, the reaction mixture is filtered and the filtrate is evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and 5% of methanol as eluent. The pure fractions are collected and the eluent is evaporated. The residue is crystallized from 4-methyl-2-pentanone. The product is filtered off and recrystallized from 4-methyl-2-pentanone, yielding 0.6 parts (10%) of 5-chloro-l-{-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 163.7C.

Example XXXI

Following the procedure of Example XXX and using equivalent amounts of the appropriate starting materials the following compounds are prepared:

1-{2-[4-(4-fluorobenzoyl)-1-piperidinyl]ethyl}-1,3-dihydro-2H-benzimidazol 2-one; mp. 163.6C;

4-chloro-3-{3-[4 (4-fluorobenzoyl)-1 piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one; mp. 138C;

5,6~-dichloro-1 {3-~4-(4~fluorobenzoyl)-1-piperidinyl]propyl}-1, 3-dihydro-2H benzimidazol-2-one; mp. 198-202C;

1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5-methyl-2H-benzimidazol-2-one; mp. 149C;

5~5~

1-~ 3-~-(4-chlorobenzoyl)-1-piperidiny~7propyl ~-l, 3-dihydro-2H-bcnzirnidazol-2-one; mp. 170.8~C; and 3-l3-~-(4-nuorobenzoyl)-1-piperidiny~7propyl} -2(3H)-be~zothiazolone; mp. 83C.

Exan~ple XXXII

A mixture of 4. 5 parts of 3- ~3-~F-(4-fluorobenzoyl)-1-piperi-dinyl7propyl }- 1, 3 -dihydro-5 -methyl - 1-(1 -methylethenyl)-ZH-benzimi-dazol-2-one, 24 parts of a concentrated hydrochloric acid solution, 80 parts of ethanol and 50 parts of water is stirred for 2 nours at room temperature. The reactic)n mi~ture is evaporated and the residue is stirred in water. The whole is alkalized with ammonium hydro~ide. The product is extracted with trichloromethane. The extract is d.ried, filtered and evaporated. The oily residue is purified by column-chroma- ;
tography over silica gel using a mixture of trichloromethane and methanol (95:5 by volume~ as eluent. The pure fractions are collected and the eluent is evaporated. The residue is crystailized from ~ methyl-2-pentanone, yielding 1 part (25%) o~ 3-~4~(4-~luo~obenzoyl)-1-piperidinyl~propyl~
1, 3-dihydro-6 -methyl-2H -benzimidazol -2 -one; mp. 149 . 7~ C . , ~;
. ' ~
Example XXXIII 'n A m~xture of 25 parts o~ .3-~2-aminoplienyl)amino7propyl~
4-piperidiny~7(4-fluorophenyl)methanone, 65 parts of carbon disul-fide and 80 parts of ethanol is stirred and re1uxed foI 15 hours. The react;on mixture is evaporated. The residue is purificd by column-chrornatography over silica gel using a mi~;ture of trichloro~nethane and ;-methanol (~5:5 -by volu~e) as eluent. The pure ~ractions are collected and the eluent is evaporated. The residue is crystallized from 2-pro-panol. The product is filtered off and dried, yielding 5 parts (18%) ofi ll-~-(2, 3-dihydro 2-thioxo-lH-benzimidazol-l -yl)propy~7-4-piperidinyll (4-fluorophenyl)methanone; mp. 149 . 2 C .
-- ~3 --~5~53 Example XXXIV
,, A miYture of 7. 24 parts of 1-(3-bromopropyl)-5-chloro~
dihydro-2H-benzimida~ol-2-one, 6. 27 parts of 4-~-(4-fluorophenyl)-1,3-dioxol~n-2-yl7piperidine, 3 parts of sodium carbonate and 1~0 parts of methylbenzene is stirred and re1uxed overnight. The reaction mi~ture is filtered over hyflo while still boiling, and the filtrate is eva-porated. The residue is boiled in 280 parts of 2,2'-oxybispropane.
While stirring, the whole is allowed to cool to room temperature. The precipitated product is filtered off and dried in vacuo at 50C, yielding 8 parts (69. 6%) of 5-chloro~ 4-/~-(4-1uorophenyl)-l, 3-dioxo-lan-2-y~7-1-piperidinyl~propyl7-1, 3-dihydro-2H-benzimidazol-2-one;
rnp. 154. 6C.
' ' ' ' ., , .
.. ' 1- , Exampl e XXXV
A mixture of 5 parts of 1-(3-chloropropyl)-1, 3-dihydrc>-3-(1- ` ;
methylethenyl)~2H-benzimidazol-2 -one, 4. 5 parts of (4-fluorophenyl) (4- pipcridinyl) methanone, 10 parts of sodium carbonate, 0. 2 parts of potasslum iodide and 80 parts of 4-methyl-2-pentanone is stirred and refluxcd overnight. After coolin~, the reaction n~ixture is poured onto ~S ater ~.nd the layers are separated. The organic phase is dricd, ~iltered and evaporated, The residue is talccll up in 2-propanone and 2-propan~l, pre~riously saturated with ~aseous hydrogen chloride, is added. Aftcr boiling Lor 30 minutes, the mixture i5 evaporated. A ~ -diluted hydrochloric acid solution is addcd to the residue and the whole is stirred and warmed at 40-45C or 1 ~lour, After tlle addition of 4_methyl-2-pentanone, the miYture is a~kalized ~ ith alnmonium hydro~ide and thc layers are scparated. The orsanic phasc is dricd, filtercd and z..nd ~vaporated, Tile residue is crystalli~cd rrGm 4-methyl-2-pentanone, The product is filtercd off and dried, yiclding 1.5 parts(20~0)of l -~3~
rluorobcnzo~ piperidinyl7propylJ-i, 3-dihydro-21-I-b2nzi~nid,^ ol-~- r one; mp. 163. 9 C0 .

-- 44, --' .

5~Si3 Example XXXVI

Following the procedure of Example XXVIII and using therein an equivalent arnount of an appropriate 1-(2-chloroethyl)- :
1, 3-dihydro-2H-benzimidazol-2-one in place of the 6-chloro-1-(3-chloropropyl)-1, 3-dihydro-2H-benYimida7.ol-2-one, the ~ollowing compounds are prepared: .

5-chloro-l- {2-~-(4-fluorobenzoyl)-1-piperidiny~7ethyl}-1, 3- ,t dihydro-2H-benzimidazol-2-one; and 6-chloro~ 2-r-(4-fluorobenzoyl)-1-piperidiny~7ethyl} -1, 3~
dihydro-2H-benzimidazol-Z-one. . - ~.
.

, Example XXXVII .~
'"~
- Following the procedure o~ Example XXXV and u~ing an equivalent amount of 3-(3-chloropropyl)-1, 3-dihydro-5-methyl- . ;
l-(l-methylethenyl)-2H-benzimidazol-2-one in place of the 1-(3-chloropropyl)-1, 3-dihydro-3-(1-methylethenyl)-2H-benzimidazol-2-one used therein, there is obtained: ,-1-~3-~-(4-fluoroben~yl)-l-piperidinyl7propyl,~-1, 3-dihydro-6-me hyl 2H-ben~imidazol-2-one.

Example XXXVIII
' The products obtained in base form in the foregoirig .
e~camples are treated with ethanolic hydrochloride in the sta~da:rd manner to produce the corresponding hydrochloric acid addition 6alt8. In turn, the latter, when treated with alkali (e. g. aqu~ous ~odium hydroxide~ yield the products in base form.

'

Claims (10)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PRO-PERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A process for preparing a chemical compound selected from the group consisting of a piperidine derivative having the formula:

(I) and the pharmaceutically acceptable acid addition salts thereof, wherein:
R is a member selected from the group consisting of hydrogen and halo;

R1 and R2 are each independently selected from the group consisting of hydrogen, halo, C1-5 alkyl and tri-fluoromethyl;
n is an integer of from 2 to 4 inclusive;
Q is a member selected from the group consisting of , and wherein R3 is C1-5 alkyl and m is an integer of from 2 to 3 inclusive; and A is a bivalent radical selected from the group consisting of , <IMG, , and -N=C(L)-wherein L is selected from the group consisting of hydrogen, C1-5 alkylthio, cyclohexyl and phenylmethyl, said bivalent radical being attached to the benzene nucleus by its hetero atom characterized by a) reaction a compound of the formula:

(II) wherein A; is the same as A, but other than , and wherein W is an appropriate ester function derived from the corresponding alcohol; with a compound of the formula:

(III) at elevated temperatures in an appropriate organic solvent, with the addition of an appropriate base; or b) removing the protecting group P from a compound of the formula (IV) by means of acid or alkaline hydrolysis in order to prepare a compound of the formula:

(I-b) wherein P is lower alkyloxycarbonyl or, a substituted ethenyl group of the formula:

wherein R4 is lower alkyl and R5 is lower alkyl or phenyl.

or c) subjecting a compound of the formula:

(V) to ring closure by heating same with a cyclizing agent, having the formula wherein X is O, S, ?N, =N-H, or ; Y is NH2, Cl, R5, H, OH, or Oalk; Z is NH2, Cl, OH, Oalk, or H; or Y and Z together represent Na-N= or S= wherein R5 is C4-6 cycloalkyl or phenyl-methyl, in order to prepare a compound of the formula:

(I-c) wherein A2 is selected from the group consisting of -NH-CO-, -NH-SC-, and N=C(L1)- wherein said L1 is selected from the group consisting of hydrogen, cycloalkyl and phenylmethyl;
or d) subjecting a compound of the formula (I) wherein A
stands for to S-alkylating procedures, by the reaction of the thione with an appropriate halo lower alkane in an appropriate organic solvent, in order to prepare a compound of the formula (I) wherein A stands for and, if desired, preparing pharmaceutically acceptable acid addition salts thereof.

2. The process of claim 1 for preparing a chemical compound selected from the group consisting of 5-chloro-1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one and the pharmaceutically acceptable acid addition salts thereof, characterized by reacting 3-(5-chloro-2,3-dihydro-2-oxo-1H-benzyimidazol-1-yl)propyl methane sulfonate with (4-fluorophenyl)-(4-piperidinyl) methanone and, if desired, preparing pharmaceutically acceptable acid addition salts thereof.

3. The process of claim 1 for preparing a chemical compound selected from the group consisting of 1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5-methyl-2H-benzimidazol-2-one and the pharmaceutically acceptable acid addition salts thereof, characterized by reactiong 3-(2,3-dihydro-5-methyl-2-oxo-1H-benzimidazol-1-yl)propyl methane sulfonate with (4-fluorophenyl)-(4-piperidinyl)methanone and, if desired, preparing pharmaceutically acceptable acid addition salts thereof.

4. The process of claim 1 for preparing a chemical compound selected from the group consisting of 1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5,6-dimethyl-2H-benzimidazol-2-one and the pharmaceutically acceptable acid addition salts thereof, characterized by reacting 1-(3-chloropropyl)-1,3-dihydro-5,6-dimethyl-2H-benzimidazol-2-one with (4-fluorophenyl)-(4-piperidinyl)methanone and, if desired, preparing pharmaceutically acceptable acid addition salts thereof.

5. The process of claim 1 for preparlng a chemical compound selected from the group consisting of 1-[3-(2,3-dihydro-2-thioxo-1H-benzimidazol-1-yl)propyl]-4-piperidinyl (4-fluorophenyl)methanone and the pharmaceutically acceptable acid addition salts thereof, characterized by cyclizing [1-{3-[(2-aminophenyl)amino]propyl}-4-piperidinyl] (4-fluoro-phenyl)methanone wlth carbon disulfide in ethanol, and, if desired, preparing pharmaceutically acceptable acid addition salts thereof.

6. A chemical compound selected from the group consisting of a piperidine derivative having the formula:

(I) and the pharmaceutically acceptable acid addition salts thereof, wherein:

R 1s a member selected from the group consisting of hydrogen and halo;
R1 and R2 are each independently selected from the group consisting of hydrogen, halo, C1-C5 alkyl and tri-fluoromethyl;
n is an integer of from 2 to 4 inclusive;

Q is a member selected from the group consisting of , and wherein R3 is C1-C5 alkyl and m is an integer of from 2 to 3 inclusive; and A is a bivalent radical selected from the group consisting of , , , and -N=C(L)-wherein L is selected from the group consisting of hydrogen, C1-C5 alkylthio, cyclohexyl and phenylmethyl, said bivalent radical being attached to the benzene nucleus by its hetero-atom whenever prepared or produced by the process of claim 1 or by any chemical equivalent thereof.

7. A chemical compound selected from the group consisting of 5-chloro-1-{3-[4-(4-fluorobenzoyl)-1-piperidinyl]propyl}-1,3-dihydro-2H-benzimidazol-2-one and the pharmaceutically acceptable acid addition salts thereof whenever prepared or produced by the process of claim 2 or by any chemical equivalent thereof.

8. A chemical compound selected from the group consisting of 1-{3-[4-(4-fluorobenzyl)-1-piperidinyl]propyl}-1,3-dihydro-5-methyl-2H-benzimidazol-2-one and the pharmaceuti-cally acceptable acid addition salts thereof whenever prepared or produced by the process of claim 3 or by any chemical equivalent thereof.

9. A chemical compound selected from the group consisting of 1-{3-[4-(4-fluoro-benzoyl)-1-piperidinyl]propyl}-1,3-dihydro-5,6-dimethyl-2H-benzimidazol-2-one and the pharmaceutically acceptable acid addition salts thereof whenever prepared or produced by the process of claim 4 or by any chemical equivalent thereof.

10. A chemical compound selected from the group consisting of 1-[3-(2,3-dihydro-2-thioxo-1H-benzimidazol-1-yl)propyl)-4-piperidinyl (4-fluoro-phenyl)methanone and the pharmaceutically acceptable acid addition salts thereof whenever prepared or produced by the process of claim 5 or by any chemical equivalent thereof.